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Advanced PowerBuilder
Limits
of a C++ User Object
C++ user objects
can add power and flexibility to your applications, but remember
that you do need prior knowledge of how to program in C++, which,
it has to be said, has a longer learning curve than PowerScript.
There are also a few limitations which you should bear in mind:
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Since a C++ user object is a non-visual user
object, you can't use it to directly link any
graphical (i.e. visual) C++ based custom controls
with your PowerBuilder application. |
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When you're linking controls with
third-party DLLs, you have to refer to the
documentation provided with the DLL to determine what
classes and methods are declared, how it responds and
its limitations in general. You would need the
complete documentation of all the classes and
functions embedded within the DLL to be able to use
it effectively. So when you're shopping around for a
third-party DLL or class library, check that the
vendor provides good technical documentation and
support. |
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You can only write user events for the
limited number of events that occur to the user
object as a whole. These user events include:
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Constructor |
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Destructor |
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DragDrop |
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DragEnter |
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DragLeave |
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DragWithin |
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RButtonDown |
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In addition to
these events, you can write custom user events for the user
object as a whole.
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